October 25, 2016

It was a gorgeous autumn weekend: brisk mornings, warm sunny afternoons, and absolutely no reason to sit at a computer screen indoors. And even though the programming on my big project at work is finished, there are still details to be looked after, so I had no time there, either. Thus, another recycled exercise today, another one that I’ve seen on the beginning-programmer message boards recently:

Write a program that determines the prime factors of a number n.

You should write at the level of a first-year programmer, nothing sophisticated. An appropriate algorithm is trial division.

Your task is to write a program to factor integers. When you are finished, you are welcome to read or run a suggested solution, or to post your own solution or discuss the exercise in the comments below.